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"Optically variable color-changing inks" section needs work
This section is garbled and doesn't read coherently; it looks like a mish-mash of edits. Can somebody who understands this technology clean up the explanations? Reify-tech (talk) 06:32, 7 June 2014 (UTC)
I tried my best at it by simply removing the commercial reference which made it sounds like disguised advertising. Hope it's better Unregistered User: lmabille 15:53, 16 January 2015 (UTC)
"False-positive testing" section is misleading
Counterfeit detector markers use a chemical interaction with the substrate, usually paper, of a document turning it a particular color. Usually a marker turns newsprint black and leaves currency or specially treated areas on a document clear or gold. The reaction and coloring varies depending upon the formulation. Banknotes, being a specially treated substrate, usually behave differently than standard newsprint or other paper and this difference is how counterfeits are detected by the markers.
I saw a video by James Randi ages ago which said that the markers which turn newsprint and copier paper black are little better than snake oil because the darkening is just iodine in the ink reacting to the starch that's used to prevent paper jams in newsprint and standard copier paper.
Any counterfeiter who knows how to produce even a half-way convincing fake of any of the features actually intended for counterfeit detection will have sourced un-starched paper, so they just lend a false sense of security. — Preceding unsigned comment added by 18.104.22.168 (talk) 14:08, 4 April 2017 (UTC)